Form for molding reinforced-concrete conduits.



G. W. CROSS.

FORM FOR MOLDING REINI'ORGED CONCRETE GONDUITS.

APPLIUATION FILED 110V. 21, 1908. 1,007, 1 8'7.

Patented Oct. 31, 1911.

s: .--TTI UNITED STATES PATENT oEEIoE.

GEORGE WVGROSS, OF FORT SMITH, ARKANSAS, ASSIGNOR TO COONIEYY CONSTRUCTION COMPANY, OF ST. LOUIS, MISSOURI, A- CORPORATION F MISSOURI.

v FORM FOR MOLDING REINFORCEDQCONCRETE CONDUITS.

Specification of Letters Patent.

Patented Oct. 31, 1911.'

Application led November 21,1908. Serial No. 463,742.

tian, Stateof Arkansas, have invented a new and useful Form for Molding Reinforced-Concrete Conduits, of which the following is a specification.

My invention relates to a device for 'use in molding pipes, conduits and the hke, particularly reinforced concrete work. I

It consists principally 1n a sheet metal core rolled into tubular form so that the edges thereof overlap and meansl whereby said core can be expanded or contracted peripherally; it also consists in means for locking said core yin expanded osition; 1t also consists in a mold adapted or coperation with said core and in means for centering said mold with respect to the core; and in means for positioning the relnforclng frame. It also consists in the arrangements and combinations of parts hereinafter* de scribed and claimed. I j In the accompanying drawing, which forms part of this specication, and wherein like symbols refer to like parts wherever they occur, Figure l is aside elevatlon of a mold embodying my invention; Fig. 2 is a vertical section taken on or about the line 2-2 of Fig. 1; Fig. 3 is a top plan view of the mold with'the top member removed; and, Fig. 4 i's a detail view of the spacing device.

The core comprises a sheet or shell l of metal rolled into cylindrical form with its marginal side portions overlapping. On the inner side ofthe core are a series of longitudinally extending ribs 2, such as angle irons or channels, which 'are rivetedv on the inside of the core to stiifen it transversely without interfering with its capaclty for binding peripherally. Located at or near the center of the core is a rod or'draw,

bar 3 extending axially thereof. Some or all of the stiifening ribs are connected to the draw bar by means of parallel links 4; that is,l all of the links that are pivotally connected to one rib are of equal length and parallel with each other. This arrangement constitutes, in effect, a toggle mechanism.-

B this arrangement, the endwise movement o the draw bar causes the ends of the links to approach or recede from the draw bar, as the case may be, and thereby correspondtice.

ing-ly collapse orexpand the shell of the core peripherally. As the links are fastened to the shell, vthe peripheral contraction or expansion of. the shell varies the angularv distance between the links; and this varia-` tion is provided for in any suitable manner. As the angular variation is not great, the necessary variation may be accommodated by a looseness -in the fastenings of the linksI or by the flexibility thereof.

In order to prevent the core from col-' lapsing accidentally in practical use, a suitable locking device is provided therefor. The device illustrated in the accompanying drawing comprises two spacing members 5 arranged near the top and the bottom, respectively, of said core. Each of these spacing members has two V-shaped slots 6 in its lower portion, which slots are spaced to t over suitable Vinwardly projecting members mounted on the respective marginal portions of the sheet. The links 4 constitute suitable projecting members-for this purpose. The uppermost or apical portions of the slots are spaced apart such a distance that, when the linksv rest therein, the core will have the diameter required in prac-,

walls of the slots serve as guides to adjust the core to the required size.

If desired, a suitable guide may be provided for positioning the distance pieces; but, in practice, it is suiicient tovhave the apical portions of their grooves so arranged that they will be radial with respect to the axis of the core when the distance 'pieces are in their predetermined .locking positions. Both of the spacing members are mounted upon a longitudinal rod 7 located close to the shell and adapted to be operated by hand or other suitable means. h

, In the construction illustrated in :the drawing, the draw bar 3 of the toggle and the rod 7 for operating the spacing members are so connected by a lost motlon device that they may be actuated by the same lifting force. For this purpose, the rod has a portion 8 which extends inwardly through a loop or link 9 provided therefor on the draw bar of the toggle mechanism, and thence the rodextends upwardly and terminates in a link l0 or other device adapted for connection to a grab hook or other` suitable hoisting apparatus. The'loop on the draw bar is of a length greater than the By this arrangement, the inclined diameter of the radial ortion of said rod, so that said rodis ree to move to a limited extent without actuating said draw bar. By this arrangement, an upward ull on the rod releases the spacing mem ers from their engagement with the links and then pulls the draw bar of the toggle mechanism.

The outer shell or member 11 of the mold consists preferably of two semicylindrical sections hinged together with ,their .meeting edges slightly overlapping. The

free ends of said sections are locked together by any suitable locking device. As'

illustrated in the v drawing, the marginal portion of one of said sections is provided with lugs 12, and the other section is provided with hinged straps or levers 13 whose lower sides are provided with V-shaped notches 14 adapted to fit over and center fsaid lugs respectively. The outer ends of in the drawing, this base member comprises 'end o an annular raised portion or rib 17 whose inner surface is of the proper size for the lower end of the core to fit when expanded; and at some distance below the top of said annular rib, the inner surface thereof is provided with lugs 18 to constitute a seat for the lower end of said core. The surface of the middle portion 19 of this annular rib or raised portion is conical and inclines downwardly until the diameter of the cone is equal to the minimum diameter of the outer shell. This point is some distance above the flat marginal portion of the base, so that a shoulder is thus formed which acts as a centering for the outer shell. The upper end of the shell is provided with a series of distance plates 20 hinged on the outer surface thereof and arranged to swing inwardly over the top of the shell and rest thereon or otherwise come to rest in a horizorital position. These hinged lates are of proper length and arrange to abut against the core and thereby center the outer shell accurately with respect to said core.

The reinforcing material 21 is made up Y into a suitable frame and is initially cen tered by bearing against the conical portion of the end member. After a suiiicient quantity of concrete has been placed in the mold, the frame may be raised by hand and the upper portion thereof centered without affectin the` roper ,centering of the lower said rame. Whenithe mold is filled with concrete, the end thereof is shaped with a top member A22 whose inner ysurface is the counterpart of ,the base piece, whereby curved forms as well as cylindrical or otherwise shaped to conform.

to vthe interior of Athev finishedy structure. Obviously, also, the devicehereinbefore described admits of considerable modification' without departing from my invention and I do not wlsh to be restricted to the details of construction above mentioned. For instance, so long as the core is sufficiently ilexible to permit of peripheral expansion and contraction, it may be made of any suitable material and in any suitable way, as by mly device' is applicable to ot er flexibly connected sections. So, too, instead i0 of making ,the shell of the core of av single member, it may be made of a series of overlapping sections.

What I claim as my invention and desire to secure by Letters Patent is:

1. A collapsible core comprising a flexible sheet rolled so that its edges overlap, a draw bar therein, a plurality of groups of parallel links connecting said draw bar to said sheet, and means for locki the side marginal portions of the sheet 1n adjusted position,

said means comprising movable spacing members adapted to t between projecting members on the inner surfaces of the re spective marginal portions and being permanently mounted in operative relation thereto.4

2. A collapsible core comprising a rolled fiexible sheet, a draw bar therein, a plurality of groups of parallel links connecting said draw bar to said sheet, and means for locking the marginal portions of the :sheetl vin adjusted position, said means comprising spacing members adapted to fit between rojecting members on the inner surface 0, ythe Inus l respective marginal portions,4 said distance pieces being mounted on a rod having an elongated slot therein, and said draw bar having a pin adapted to ooperate with the lower end of said slot. 1

3. A collapsible core comprising a rolled flexible sheet, a draw bar therein, a plurality of groups of parallel links connecting` said draw bar to said sheet, and means for locking said marginal portions of the sheet in adjusted position,'sa1d means comprising spacingv members adapted to fit between projecting memberson the inner surface of the respective marginal portions, and said distance pieces being connected to a4 hanger draw bar.

' a draw bar therein,

which has a lost motion connection with the 4. A collapsible core com rising a flexible sheet, rolled so that its si parallellinks connecting said draw .bar to said sheet, and permanently mounted means for locking said marginal portions of the sheet in adjusted position, said means comprising members having V-shaped ,slots adapted to fit over projecting members on the inner surface of said core at the top ,and

e edges overlap, a plurality of groups of- 'bottom thereof, andthereby prevent the expansion and contraction of said c'ore.

In testimony whereof I have signed my 15 l GEO. CROSS. Witnesses: R. D. SALISBURY,

l M. F. SMITH. 

